Input Device Layers and Nesting

ABSTRACT

Input device layer and nesting techniques are described. In one or more implementations, an input device includes a pressure sensitive key assembly including a substrate having a plurality of hardware elements secured to a surface. The input device also includes one or more layers disposed proximal to the surface, the one or more layers having respective openings configured to nest the one or more hardware elements therein.

RELATED APPLICATIONS

This application claims priority under 35 U.S.C. §119(e) to thefollowing U.S. Provisional Patent Applications, the entire disclosuresof each of these applications being incorporated by reference in theirentirety:

-   U.S. Provisional Patent Application No. 61/606,321, filed Mar. 2,    2012, Attorney Docket Number 336082.01, and titled “Screen Edge;”-   U.S. Provisional Patent Application No. 61/606,301, filed Mar. 2,    2012, Attorney Docket Number 336083.01, and titled “Input Device    Functionality;”-   U.S. Provisional Patent Application No. 61/606,313, filed Mar. 2,    2012, Attorney Docket Number 336084.01, and titled “Functional    Hinge;”-   U.S. Provisional Patent Application No. 61/606,333, filed Mar. 2,    2012, Attorney Docket Number 336086.01, and titled “Usage and    Authentication;”-   U.S. Provisional Patent Application No. 61/613,745, filed Mar. 21,    2012, Attorney Docket Number 336086.02, and titled “Usage and    Authentication;”-   U.S. Provisional Patent Application No. 61/606,336, filed Mar. 2,    2012, Attorney Docket Number 336087.01, and titled “Kickstand and    Camera;” and-   U.S. Provisional Patent Application No. 61/607,451, filed Mar. 6,    2012, Attorney Docket Number 336143.01, and titled “Spanaway    Provisional;” and further this application incorporates the    following applications by reference in their entirety:

U.S. patent application Ser. No. ______, filed May 14, 2012, AttorneyDocket Number 336554.01, and titled “Flexible Hinge and RemovableAttachment;” and

-   U.S. patent application Ser. No. ______, filed May 14, 2012,    Attorney Docket Number 336564.01, and titled “Input Device    Assembly.”

BACKGROUND

Mobile computing devices have been developed to increase thefunctionality that is made available to users in a mobile setting. Forexample, a user may interact with a mobile phone, tablet computer, orother mobile computing device to check email, surf the web, composetexts, interact with applications, and so on. However, traditionalmobile computing devices often employed a virtual keyboard that wasaccessed using touchscreen functionality of the device. This wasgenerally employed to maximize an amount of display area of thecomputing device.

Use of the virtual keyboard, however, could be frustrating to a userthat desired to provide a significant amount of inputs, such as to entera significant amount of text to compose a long email, document, and soforth. Thus, conventional mobile computing devices were often perceivedto have limited usefulness for such tasks, especially in comparison withease at which users could enter text using a conventional keyboard,e.g., of a conventional desktop computer. Use of the conventionalkeyboards, though, with the mobile computing device could decrease themobility of the mobile computing device and thus could make the mobilecomputing device less suited for its intended use in mobile settings.

SUMMARY

Input device layer and nesting techniques are described. In one or moreimplementations, an input device includes a pressure sensitive keyassembly including a substrate having a plurality of hardware elementssecured to a surface thereof. The input device also includes one or morelayers disposed proximal to the surface, the one or more layers havingrespective openings configured to nest the one or more hardware elementstherein.

In one or more implementations, an apparatus includes a sensorsubstrate, a flexible contact layer, and one or more layers. The sensorsubstrate has one or more conductors disposed on a first side of thesensor substrate and one or more surface mount hardware elementsdisposed on a second side of the sensor substrate that is opposite thefirst side. The flexible contact layer is spaced apart from the sensorsubstrate and configured to flex in response to an application ofpressure to contact the sensor substrate to initiate an input for acomputing device that is communicatively coupled to the input device.The one or more layers are disposed on the second side of the sensorsubstrate and have one or more openings therein such that at least aportion of the one or more surface mount hardware elements is disposedthrough the one or more openings thereby nesting the one or more surfacemount hardware elements within the one or more layers.

In one or more implementations, a keyboard includes a key assemblyincluding a substrate having a hardware element attached to a surfacethereof, the hardware element configured to process signals receivedfrom the key assembly into a respective human interface device (HID)compliant output. The keyboard also includes one or more layers disposedproximal to the surface of the sensor substrate, the one or more layershaving one or more openings therein such that at least a portion of thehardware element is disposed through the one or more openings therebynesting the one or more hardware elements within the one or more layers.

This Summary is provided to introduce a selection of concepts in asimplified form that are further described below in the DetailedDescription. This Summary is not intended to identify key features oressential features of the claimed subject matter, nor is it intended tobe used as an aid in determining the scope of the claimed subjectmatter.

BRIEF DESCRIPTION OF THE DRAWINGS

The detailed description is described with reference to the accompanyingfigures. In the figures, the left-most digit(s) of a reference numberidentifies the figure in which the reference number first appears. Theuse of the same reference numbers in different instances in thedescription and the figures may indicate similar or identical items.Entities represented in the figures may be indicative of one or moreentities and thus reference may be made interchangeably to single orplural forms of the entities in the discussion.

FIG. 1 is an illustration of an environment in an example implementationthat is operable to employ the techniques described herein.

FIG. 2 depicts an example implementation of an input device of FIG. 1 asshowing a flexible hinge in greater detail.

FIG. 3 depicts an example implementation showing a perspective view of aconnecting portion of FIG. 2 that includes mechanical couplingprotrusions and a plurality of communication contacts.

FIG. 4 depicts a plurality of layers of the input device of FIG. 2 in aperspective exploded view.

FIG. 5 depicts an example of a cross-sectional view of a pressuresensitive key of a keyboard of the input device of FIG. 2.

FIG. 6 depicts an example of a pressure sensitive key of FIG. 5 ashaving pressure applied at a first location of a flexible contact layerto cause contact with a corresponding first location of a sensorsubstrate.

FIG. 7 depicts an example of the pressure sensitive key of FIG. 5 ashaving pressure applied at a second location of the flexible contactlayer to cause contact with a corresponding second location of thesensor substrate.

FIG. 8 illustrates an example of the flexible contact layer of a singlepressure sensitive key that is configured to normalize outputs generatedat a plurality of locations of the switch.

FIG. 9 depicts an example of a pressure sensitive key of FIG. 5 thatincludes a plurality of sensors to detect pressure at differentlocations.

FIG. 10 depicts an example of conductors of a sensor substrate of apressure sensitive key that is configured to normalize signals generatedat different locations of the pressure sensitive key.

FIG. 11 depicts an example of a pressure sensitive key of FIG. 5 asemploying a force concentrator layer.

FIG. 12 an example of the pressure sensitive key of FIG. 11 as havingpressure applied at a plurality of different locations of the forceconcentrator layer to cause a flexible contact layer to contact a sensorsubstrate.

FIG. 13 illustrates an example of a view of a cross section of akeyboard that includes a plurality of pressure sensitive keys thatemploy the force concentrator layer.

FIG. 14 depicts an example implementation showing a support layer thatis configured to support operation of the flexible hinge as well asprotect components of the input device during this operation.

FIG. 15 depicts a bottom view of a pressure sensitive key of FIG. 5 ashaving a flexible contact layer secured at a plurality of locationsalong edges of the key.

FIG. 16 depicts another version of FIG. 15 in which a securing portionis moved to a different location along an edge of the key.

FIG. 17 depicts an example of an adhesive layer applied as part of akeyboard having a plurality of keys in which different arrangements ofadhesive are used for different keys.

FIG. 18 depicts an example of surface mount hardware elements that maybe used to support functionality of the input device of FIG. 1.

FIG. 19 illustrates an example implementation in which the surface mounthardware element of FIG. 18 is depicted as being nested in one or morelayers of the input device.

FIG. 20 illustrates an example system including various components of anexample device that can be implemented as any type of computing deviceas described with reference to the other figures to implementembodiments of the techniques described herein.

DETAILED DESCRIPTION Overview

Input devices may be configured to support a thin form factor, such asapproximately three and a half millimeters and smaller. However,components that may be used to support functionality of the input devicemay have a height that may interfere with the thin form factor.Therefore, designers using conventional techniques may be forced todecide whether to include the components but add a significant amount ofthickness to the input device or forgo use of the components.

Input device layer and nesting techniques are described. In one or moreimplementations, layers of an input device are configured to nestsurface mount hardware elements. The input device, for example, may beconfigured as a pressure sensitive keyboard that includes surface mounthardware elements to support functionality of the device. This mayinclude a processor (e.g., to process signals of the keys into an HIDcompliant input), sensors (e.g., accelerometers), a touch controller(e.g., to process signals of a touch pad), linear regulators, anauthentication integrated circuit (e.g., to authenticate the inputdevice for operation with a computing device), and so on. Layers may beconfigured to include openings such that at least a portion of thehardware elements may be disposed through the openings. In this way, aneffect of the surface mount hardware elements on a thickness of theinput device may be reduced, such as to support a form factor in whichthe input device may act as a cover for the computing device whenconfigured as a tablet computer. Further discussion of these and othertechniques may be found in relation to the following sections.

In the following discussion, an example environment is first describedthat may employ the techniques described herein. Example procedures arethen described which may be performed in the example environment as wellas other environments. Consequently, performance of the exampleprocedures is not limited to the example environment and the exampleenvironment is not limited to performance of the example procedures.

Example Environment

FIG. 1 is an illustration of an environment 100 in an exampleimplementation that is operable to employ the techniques describedherein. The illustrated environment 100 includes an example of acomputing device 102 that is physically and communicatively coupled toan input device 104 via a flexible hinge 106. The computing device 102may be configured in a variety of ways. For example, the computingdevice 102 may be configured for mobile use, such as a mobile phone, atablet computer as illustrated, and so on. Thus, the computing device102 may range from full resource devices with substantial memory andprocessor resources to a low-resource device with limited memory and/orprocessing resources. The computing device 102 may also relate tosoftware that causes the computing device 102 to perform one or moreoperations.

The computing device 102, for instance, is illustrated as including aninput/output module 108. The input/output module 108 is representativeof functionality relating to processing of inputs and rendering outputsof the computing device 102. A variety of different inputs may beprocessed by the input/output module 108, such as inputs relating tofunctions that correspond to keys of the input device 104, keys of avirtual keyboard displayed by the display device 110 to identifygestures and cause operations to be performed that correspond to thegestures that may be recognized through the input device 104 and/ortouchscreen functionality of the display device 110, and so forth. Thus,the input/output module 108 may support a variety of different inputtechniques by recognizing and leveraging a division between types ofinputs including key presses, gestures, and so on.

In the illustrated example, the input device 104 is configured as akeyboard having a QWERTY arrangement of keys although other arrangementsof keys are also contemplated. Further, other non-conventionalconfigurations are also contemplated, such as a game controller,configuration to mimic a musical instrument, and so forth. Thus, theinput device 104 and keys incorporated by the input device 104 mayassume a variety of different configurations to support a variety ofdifferent functionality.

As previously described, the input device 104 is physically andcommunicatively coupled to the computing device 102 in this examplethrough use of a flexible hinge 106. The flexible hinge 106 is flexiblein that rotational movement supported by the hinge is achieved throughflexing (e.g., bending) of the material forming the hinge as opposed tomechanical rotation as supported by a pin, although that embodiment isalso contemplated. Further, this flexible rotation may be configured tosupport movement in one direction (e.g., vertically in the figure) yetrestrict movement in other directions, such as lateral movement of theinput device 104 in relation to the computing device 102. This may beused to support consistent alignment of the input device 104 in relationto the computing device 102, such as to align sensors used to changepower states, application states, and so on.

The flexible hinge 106, for instance, may be formed using one or morelayers of fabric and include conductors formed as flexible traces tocommunicatively couple the input device 104 to the computing device 102and vice versa. This communication, for instance, may be used tocommunicate a result of a key press to the computing device 102, receivepower from the computing device, perform authentication, providesupplemental power to the computing device 102, and so on. The flexiblehinge 106 may be configured in a variety of ways, further discussion ofwhich may be found in relation to the following figure.

FIG. 2 depicts an example implementation 200 of the input device 104 ofFIG. 1 as showing the flexible hinge 106 in greater detail. In thisexample, a connection portion 202 of the input device is shown that isconfigured to provide a communicative and physical connection betweenthe input device 104 and the computing device 102. In this example, theconnection portion 202 has a height and cross section configured to bereceived in a channel in the housing of the computing device 102,although this arrangement may also be reversed without departing fromthe spirit and scope thereof.

The connection portion 202 is flexibly connected to a portion of theinput device 104 that includes the keys through use of the flexiblehinge 106. Thus, when the connection portion 202 is physically connectedto the computing device the combination of the connection portion 202and the flexible hinge 106 supports movement of the input device 104 inrelation to the computing device 102 that is similar to a hinge of abook.

For example, rotational movement may be supported by the flexible hinge106 such that the input device 104 may be placed against the displaydevice 110 of the computing device 102 and thereby act as a cover. Theinput device 104 may also be rotated so as to be disposed against a backof the computing device 102, e.g., against a rear housing of thecomputing device 102 that is disposed opposite the display device 110 onthe computing device 102.

Naturally, a variety of other orientations are also supported. Forinstance, the computing device 102 and input device 104 may assume anarrangement such that both are laid flat against a surface as shown inFIG. 1. In another instance, a typing arrangement may be supported inwhich the input device 104 is laid flat against a surface and thecomputing device 102 is disposed at an angle to permit viewing of thedisplay device 110, e.g., such as through use of a kickstand disposed ona rear surface of the computing device 102. Other instances are alsocontemplated, such as a tripod arrangement, meeting arrangement,presentation arrangement, and so forth.

The connecting portion 202 is illustrated in this example as includingmagnetic coupling devices 204, 206, mechanical coupling protrusions 208,210, and a plurality of communication contacts 212. The magneticcoupling devices 204, 206 are configured to magnetically couple tocomplementary magnetic coupling devices of the computing device 102through use of one or more magnets. In this way, the input device 104may be physically secured to the computing device 102 through use ofmagnetic attraction.

The connecting portion 202 also includes mechanical coupling protrusions208, 210 to form a mechanical physical connection between the inputdevice 104 and the computing device 102. The mechanical couplingprotrusions 208, 210 are shown in greater detail in the followingfigure.

FIG. 3 depicts an example implementation 300 shown a perspective view ofthe connecting portion 202 of FIG. 2 that includes the mechanicalcoupling protrusions 208, 210 and the plurality of communicationcontacts 212. As illustrated, the mechanical coupling protrusions 208,210 are configured to extend away from a surface of the connectingportion 202, which in this case is perpendicular although other anglesare also contemplated.

The mechanical coupling protrusions 208, 210 are configured to bereceived within complimentary cavities within the channel of thecomputing device 102. When so received, the mechanical couplingprotrusions 208, 210 promote a mechanical binding between the deviceswhen forces are applied that are not aligned with an axis that isdefined as corresponding to the height of the protrusions and the depthof the cavity.

For example, when a force is applied that does coincide with thelongitudinal axis described previously that follows the height of theprotrusions and the depth of the cavities, a user overcomes the forceapplied by the magnets solely to separate the input device 104 from thecomputing device 102. However, at other angles the mechanical couplingprotrusion 208, 210 are configured to mechanically bind within thecavities, thereby creating a force to resist removal of the input device104 from the computing device 102 in addition to the magnetic force ofthe magnetic coupling devices 204, 206. In this way, the mechanicalcoupling protrusions 208, 210 may bias the removal of the input device104 from the computing device 102 to mimic tearing a page from a bookand restrict other attempts to separate the devices.

The connecting portion 202 is also illustrated as including a pluralityof communication contacts 212. The plurality of communication contacts212 is configured to contact corresponding communication contacts of thecomputing device 102 to form a communicative coupling between thedevices. The communication contacts 212 may be configured in a varietyof ways, such as through formation using a plurality of spring loadedpins that are configured to provide a consistent communication contactbetween the input device 104 and the computing device 102. Therefore,the communication contact may be configured to remain during minormovement of jostling of the devices. A variety of other examples arealso contemplated, including placement of the pins on the computingdevice 102 and contacts on the input device 104.

FIG. 4 depicts a plurality of layers of the input device 104 in aperspective exploded view 400. At top, an outer layer 402 is shown whichmay be configured using an embossed fabric (e.g., 0.6 millimeterpolyurethane) in which the embossing is used to provide indications ofunderlying keys as well as indications of respective functions of thekeys.

A force concentrator 404 is disposed beneath the outer layer 402. Theforce concentrator 402 may be configured to provide a mechanical filter,force direction, and to hide witness lines of underlying components asfurther described in the “Force Concentrator” section below.

Below the force concentrator 404 in this example is a pressure sensitivekey assembly 406. The pressure sensitive key assembly 406 may includelayers used to implement pressure sensitive keys, as further describedin the “Pressure Sensitive Key” section below.

A support layer 408 is illustrated below the pressures sensitive key 406assembly. The support layer 408 is configured to support the flexiblehinge 106 and conductors included therein from damage. Furtherdiscussion of the support layer 408 may be found in relation to the“Support Layer” section.

An adhesive layer 410 is illustrated as disposed beneath the supportlayer 408 and above a support board 412 which is configured to addmechanical stiffness to an input portion of the input device 104. Theadhesive layer 410 may be configured in a variety of ways to secure thesupport board 412 to the support layer 408. The adhesive layer 410, forinstance, may be configured to include a dot matrix of adhesive on bothsides of the layer. Therefore, air is permitted to escape as the layersare rolled together, thereby reducing wrinkles and air bubbles betweenthe layers. In the illustrated example, the adhesive layer 410 alsoincludes a nesting channel configured to support flexible printedcircuit routing, e.g., between controllers, sensors, or other modulesand the pressure sensitive keys and/or communication contacts of theconnection portion 202. Beneath the support board 412 is a backer layer414 and an outer surface 416. The outer surface 416 may be formed from amaterial that is the same as or different from the other outer surface402.

Pressure Sensitive Key Assembly

FIG. 5 depicts an example of a cross-sectional view of a pressuresensitive key 500 of a keyboard of the input device 104 of FIG. 2 thatforms the pressure sensitive key assembly 406. The pressure sensitivekey 500 in this example is illustrated as being formed using a flexiblecontact layer 502 (e.g., Mylar) that is spaced apart from the sensorsubstrate 504 using a spacer layer 508, 408, which may be formed asanother layer of Mylar, formed on the sensor substrate 504, and so on.In this example, the flexible contact layer 502 does not contact thesensor substrate 504 absent application of pressure against the flexiblecontact layer 502.

The flexible contact layer 502 in this example includes a forcesensitive ink 510 disposed on a surface of the flexible contact layer502 that is configured to contact the sensor substrate 504. The forcesensitive ink 510 is configured such that an amount of resistance of theink varies directly in relation to an amount of pressure applied. Theforce sensitive ink 510, for instance, may be configured with arelatively rough surface that is compressed against the sensor substrate504 upon an application of pressure against the flexible contact layer502. The greater the amount of pressure, the more the force sensitiveink 510 is compressed, thereby increasing conductivity and decreasingresistance of the force sensitive ink 510. Other conductors may also bedisposed on the flexible contact layer 502 without departing form thespirit and scope therefore, including other types of pressure sensitiveand non-pressure sensitive conductors.

The sensor substrate 504 includes one or more conductors 512 disposedthereon that are configured to be contacted by the force sensitive ink510 of the flexible contact layer 502. When contacted, an analog signalmay be generated for processing by the input device 104 and/or thecomputing device 102, e.g., to recognize whether the signal is likelyintended by a user to provide an input for the computing device 102. Avariety of different types of conductors 512 may be disposed on thesensor substrate 504, such as formed from a variety of conductivematerials (e.g., silver, copper), disposed in a variety of differentconfigurations as further described in relation to FIG. 9, and so on.

FIG. 6 depicts an example 600 of the pressure sensitive key 500 of FIG.5 as having pressure applied at a first location of the flexible contactlayer 502 to cause contact of the force sensitive ink 510 with acorresponding first location of the sensor substrate 504. In thefollowing discussion, FIGS. 6 and 7 are compared and thus the use ofterms such as “relative” refers to a comparison performed betweenrespective parts of the figures and discussion.

The pressure is illustrated through use of an arrow in FIG. 6 and may beapplied in a variety of ways, such as by a finger of a user's hand,stylus, pen, and so on. In this example, the first location at whichpressure is applied as indicated by the arrow is located generally neara center region of the flexible contact layer 502 that is disposedbetween the spacer layers 506, 508. Due to this location, the flexiblecontact layer 502 may be considered generally flexible and thusresponsive to the pressure.

This flexibility permits a relatively large area of the flexible contactlayer 502, and thus the force sensitive ink 510, to contact theconductors 512 of the sensor substrate 504. Thus, a relatively strongsignal may be generated. Further, because the flexibility of theflexible contact layer 502 is relatively high at this location, arelatively large amount of the force may be transferred through theflexible contact layer 502, thereby applying this pressure to the forcesensitive ink 510. As previously described, this increase in pressuremay cause a corresponding increase in conductivity of the forcesensitive ink and decrease in resistance of the ink. Thus, therelatively high amount of flexibility of the flexible contact layer atthe first location may cause a relatively stronger signal to begenerated in comparison with other locations of the flexible contactlayer 502 that located closer to an edge of the key, an example of whichis described in relation to the following figure.

FIG. 7 depicts an example 700 of the pressure sensitive key 500 of FIG.5 as having pressure applied at a second location of the flexiblecontact layer 502 to cause contact with a corresponding second locationof the sensor substrate 504. In this example, the second location ofFIG. 6 at which pressure is applied is located closer to an edge of thepressure sensitive key (e.g., closer to an edge of the spacer layer 508)than the first location of FIG. 5. Due to this location, the flexiblecontact layer 502 has reduced flexibility when compared with the firstlocation and thus less responsive to pressure.

This reduced flexibility may cause a reduction in an area of theflexible contact layer 502, and thus the force sensitive ink 510, thatcontacts the conductors 512 of the sensor substrate 504. Thus, a signalproduced at the second location may be weaker than a signal produced atthe first location of FIG. 6 for similar amounts of pressure.

Further, because the flexibility of the flexible contact layer 502 isrelatively low at this location, a relatively low amount of the forcemay be transferred through the flexible contact layer 502, therebyreducing the amount of pressure transmitted to the force sensitive ink510. As previously described, this decrease in pressure may cause acorresponding decrease in conductivity of the force sensitive ink andincrease in resistance of the ink in comparison with the first locationof FIG. 5. Thus, the reduced flexibility of the flexible contact layer502 at the second location in comparison with the first location maycause a relatively weaker signal to be generated. Further, thissituation may be exacerbated by a partial hit in which a smaller portionof the user's finger is able to apply pressure at the second location ofFIG. 7 in comparison with the first location of FIG. 6.

However, as previously described techniques may be employed to normalizeoutputs produced by the switch at the first and second locations. Thismay be performed in a variety of ways, such as through configuration ofthe flexible contact layer 502 as described in relation to FIG. 8, useof a plurality of sensors as described in relation to FIG. 9,configuration of the sensor substrate 504 as described in relation toFIG. 10, use of a force concentrator layer as described in relation toFIGS. 11-13, use of securing as described in relation to FIGS. 14-16,and combinations thereof as further described in relation to thefollowing sections.

Flexible Contact Layer

FIG. 8 illustrates an example 800 of the flexible contact layer of asingle pressure sensitive key that is configured to normalize outputsgenerated at a plurality of locations of the switch. In this example, aview of the “bottom” or “underside” of the flexible contact layer 502 ofFIG. 5 is shown that is configured to contact the conductors 512 of thesensor substrate 504.

The flexible contact layer 502 is illustrated as having first and secondsensing areas 802, 804. The first sensing area 802 in this examplecorresponds generally to the first location at which pressure wasapplied in FIG. 6 and the second sensing area 804 corresponds generallyto the second location at which pressure was applied in FIG. 7.

As previously described, flexing of the flexible contact layer 502 dueto changes in distances from an edge of the switch may cause relativelystronger signals to be generated as distances increase from an edge ofthe key. Therefore, in this example the first and second sensing areas802, 804 are configured to normalize the signals 806 generated at thedifferent locations. This may be done in a variety of ways, such as byhaving a higher conductivity and less resistance at the second sensingarea 804 in comparison with the first sensing area 802.

The differences in conductivity and/or resistance may be achieved usinga variety of techniques. For example, one or more initial layers of aforce sensitive ink may be applied to the flexible contact layer 502that covers the first and second sensing areas 804, 802, such as throughuse of a silk screen, printing process, or other process by which theink may be disposed against the surface. One or more additional layersmay then be applied to the second sensing area 704 and not the firstsensing area 802.

This causes the second sensing area 804 to have a greater amount (e.g.,thickness) of the force sensitive ink than the first sensing area 802for a given area, which causes a corresponding increase in conductivityand decrease in resistance. Therefore, this technique may serve to atleast partially counteract the differences in flexibility of theflexible contact layer 502 at different locations. In this example, anincreased height of the force sensitive ink at the second sensing area804 may also act to reduce an amount of flexing involved in generatingcontact with the conductors 512 of the sensor substrate 504, which mayalso help to normalize the signals.

The differences in conductivity and/or resistance at the first andsecond sensing areas 802, 804 may be achieved in a variety of otherways. For example, a first force sensitive ink may be applied at thefirst sensing area 802 and a second force sensitive ink having a higherconductivity and/or resistance may be applied at the second sensing area804. Further, although an arrangement of first and second sensing areas802, 804 as concentric square is shown in FIG. 8, a variety of otherarrangements may also be employed, such as to further increasesensitivity at the corners of the switch, employ more than two sensingareas having different sensitivities to pressure, use of a gradient ofconductivities, and so forth. Other examples are also contemplated, suchas to support use of a plurality of sensors for a single key, an exampleof which is described in relation to the following figure.

FIG. 9 depicts an example 900 of a pressure sensitive key 500 of FIG. 5that includes a plurality of sensors to detect pressure at differentlocations. As previously described, miss hits and limitations offlexibility may cause reduced performance at edges of a pressuresensitive key.

Accordingly, in this example a first sensor 902 and a second sensor 904are employed to provide respective first and second sensor signals 906,908, respectively. Further, the second sensor 904 is configured to haveincreased sensitivity (e.g., higher conductivity and/or lowerresistance) that the first sensor 902. This may be achieved in a varietyof ways, such as through different conductors and configurations of theconductors to act as sensors as part of the sensor substrate 504. Otherconfigurations of the sensor substrate 504 may also be made to normalizesignals generated by the pressure sensitive key at different locationsof the key, an example of which is described in relation to thediscussion of the following figure.

Sensor Substrate

FIG. 10 depicts an example of conductors 512 of a sensor substrate 504that are configured to normalize signals generated at differentlocations of a pressure sensitive key. In this example, conductors 512of the sensor substrate 504 are configured in first and second portions1002, 1004 of inter-digitated trace fingers. Surface area, amount ofconductors, and gaps between the conductors are used in this example toadjust sensitivity at different locations of the sensor substrate 504.

For example, pressure may be applied to a first location 1006 may causea relatively larger area of the force sensitive ink 510 of the flexiblecontact layer 502 to contact the conductors in comparison with a secondlocation 1008 of the sensor substrate 504. As shown in the illustratedexample, an amount of conductor contacted at the first location 1006 isnormalized by an amount of conductor contacted at the second portion1006 through use of gap spacing and conductor size. In this way, byusing smaller conductors (e.g., thinner fingers) and larger gaps at thecenter of the key as opposed to the edge of the key specific performancecharacteristics for the keys may be adjusted to suite typical user inputscenarios. Further, these techniques for configuring the sensorsubstrate 504 may be combined with the techniques described forconfiguring the flexible contact layer 502 to further promotenormalization and desired user input scenarios.

Returning again to FIG. 2, these techniques may also be leveraged tonormalize and support desired configuration of different keys, such asto normalize a signal generated by a first key of a keyboard of theinput device 104 with a signal generated by a second key of thekeyboard. As shown in the QWERTY arrangement of FIG. 2 (although this isequally applicable to other arrangements), users are more likely toapply greater typing pressure to a home row of keys located at a centerof the input device 104 than keys located closer to the edges of thedevice. This may include initiation using fingernails of a user's handfor the shift key row as well as an increased distance to reach for thenumbers, different strengths of different fingers (index versus pinkyfinger), and so on.

Accordingly, the techniques described above may also be applied tonormalize signals between these keys, such as to increase sensitivity ofnumber keys in relation to home row keys, increase sensitivity of“pinky” keys (e.g., the letter “a” and semicolon key) as opposed toindex finger keys (e.g., the letters “f,” “g,” “h,” and “j”), and soforth. A variety of other examples are also contemplated involvingchanges to sensitivity, such as to make keys having a smaller surfacearea (e.g., the delete button in the figure) more sensitive incomparison with larger keys, such as the shift keys, spacebar, and soforth.

Force Concentrator

FIG. 11 depicts an example 1100 of a pressure sensitive key of FIG. 4 asemploying a force concentrator 404 of FIG. 4. The force concentrator 404includes a force concentrator layer 1102 and a pad 1104. The forceconcentrator layer 1102 may be configured from a variety of materials,such as a flexible material (e.g., Mylar) that is capable of flexingagainst the flexible contact layer 502. The force concentrator 404 maybe employed to improve consistency of the contact of the flexiblecontact layer 502 with the sensor substrate 504 as well as otherfeatures.

As described above, the force concentrator layer 1102 in this instanceincludes a pad 1104 disposed thereon that is raised from a surface ofthe force concentrator layer 1102. Thus, the pad 1104 is configured as aprotrusion to contact the flexible contact layer 502. The pad 1104 maybe formed in a variety of ways, such as formation as a layer (e.g.,printing, deposition, forming, etc.) on a substrate of the forceconcentrator layer 1102 (e.g., Mylar), as an integral part of thesubstrate itself, and so on.

FIG. 12 an example 1200 of the pressure sensitive key of FIG. 11 ashaving pressure applied at a plurality of different locations of theforce concentrator layer 1102 to cause the flexible contact layer 502 tocontact the sensor substrate 504. The pressure is again illustratedthrough use of arrow, which in this instance include first, second, andthird locations 1202, 1204, 1206 which are positioned at distances thatare respectively closer to an edge of the key, e.g., an edge defined bythe spacer layer 508, 508.

As illustrated, the pad 1104 is sized so as to permit the flexiblecontact layer 502 to flex between the spacer layer 508, 508. The pad1104 is configured to provide increased mechanical stiffness and thusimproved resistance to bending and flexing, e.g., as in comparison witha substrate (e.g., Mylar) of the force concentrator layer 1102.Therefore, when the pad 1104 is pressed against the flexible contactlayer 502, the flexible contact layer 502 has a decreased bend radius asillustrated through comparison of FIG. 12 with FIGS. 6 and 7.

Thus, the bending of the flexible contact layer 502 around the pad 1104may promote a generally consistent contact area between the forcesensitive ink 510 and the conductors 512 of the sensor substrate 504.This may promote normalization of a signal produced by the key.

The pad 1104 may also act to spread a contact area of a source of thepressure. A user, for example, may press against the force concentratorlayer 1102 using a fingernail, a tip of a stylus, pen, or other objectthat has a relatively small contact area. As previously described thiscould result in correspondingly small contact area of the flexiblecontact layer 502 that contacts the sensor substrate 504, and thus acorresponding decrease in signal strength.

However, due to the mechanical stiffness of the pad 1104, this pressuremay be spread across an area of the pad 1104 that contacts the flexiblecontact layer 502, which is then spread across an area of the flexiblecontact layer 502 that correspondingly bends around the pad 1104 tocontact the sensor substrate 504. In this way, the pad 1104 may be usedto normalize a contact area between the flexible contact layer 502 andthe sensor substrate 504 that is used to generate a signal by thepressure sensitive key.

The pad 1104 may also act to channel pressure, even if this pressure isapplied “off center.” As previously described in relation to FIGS. 6 and7, the flexibility of the flexible contact layer 502 may depend at leastpartially on a distance from an edge of the pressure sensitive key,e.g., an edge defined by the spacer layer 508, 508 in this instance.

The pad 1104, however, may be used to channel pressure to the flexiblecontact layer 502 to promote generally consistent contact. For example,pressure applied at a first location 1202 that is positioned at ageneral center region of the force concentrator layer 1102 may causecontact that is similar to contact achieved when pressure applied at asecond location 1204 that is positioned at an edge of the pad 1104.Pressures applied outside of a region of the force concentrator layer1102 defined by the pad 1104 may also be channeled through use of thepad 1104, such as a third position 1206 that is located outside of theregion defined by the pad 1104 but within an edge of the key. A positionthat is located outside of a region of the force concentrator layer 1102defined by the spacer layer 508, 508 may also be channeled to cause theflexible contact layer 502 to contact the sensor substrate 504, anexample of which is defined in relation to the following figure.

FIG. 13 illustrates an example of a view of a cross section of akeyboard 1300 that includes a plurality of pressure sensitive keys thatemploy the force concentrator. The keyboard 1300 in this exampleincludes first and second pressure sensitive keys 1302, 1304. Thepressure sensitive keys 1302, 1304 share a force concentrator layer1102, a flexible contact layer 502, a sensor substrate 504, and a spacerlayer 508 as before. Each of the pressure sensitive keys 1302, 1304 inthis example has a respective pad 1306, 1308 that is configured tochannel pressure to cause contact between a respective portion of theflexible contact layer 502 and sensor substrate 504.

As previously described, limited flexibility at the edges ofconventional pressure sensitive keys could result in an inability of thekeys to recognize pressure applied at the edges of the keys. This couldcause “dead zones” in which the input device 104 could not recognizeapplied pressures. However, through use of the force concentrator layer1102 and channeling of pressure supported by the pads 1306, 1308 theexistence of dead zones may be reduced and even eliminated.

For example, a location 1310 is illustrated through use of an arrow thatis disposed between the first and second pressure sensitive keys 1302,1304. In this instance, the location 1310 is disposed over the spacerlayer 508 and closer to the first pressure sensitive key 1302 than thesecond pressure sensitive key 1304.

Accordingly, the pad 1306 of the first pressure sensitive key 1302 maychannel a greater amount of the pressure than the pad 1308 of the secondpressure sensitive key 1304. This may result in a stronger signal beingproduce by the first pressure sensitive key 1302 than the secondpressure sensitive key 1304, a signal being generated at just the firstpressures sensitive key 1302 and not the second pressure sensitive key1304, and so forth. Regardless, modules of the input device 104 and/orthe computing device 102 may then determine a likely intent of a userregarding which of the keys is to be employed by processing the signalsgenerated by the keys. In this way, the force concentrator layer 1102may mitigate against dead zones located between the keys by increasingan area that may be used to activate the key through channeling.

The force concentrator layer 1102 may also be used to perform mechanicalfiltering of pressures applied against the keys. A user, for instance,when typing a document may choose to rest one or more fingers of a handagainst a surface of the keys but not wish to activate the key. Withoutthe force concentrator layer 1102, therefore, processing of inputs fromthe pressure sensitive keys may be complicated by determining whether anamount and/or duration of pressure applied to the key is likely intendedto activate the key.

However, in this example the force concentrator layer 1102 may beconfigured for use with the flexible contact layer to mechanicallyfilter inputs that are not likely to be intended by a user to activatethe key. The force concentrator layer 1102, for instance, may beconfigured to employ a threshold that in combination with the flexiblecontact layer 502 defines an amount of pressure to be employed toactuate the key. This may include an amount of pressure that issufficient to cause the flexible contact layer 502 and the forcesensitive ink 510 disposed thereon to contact conductors 512 of thesensor substrate to generate a signal that is recognizable as an inputby the input device 104 and/or computing device 102.

In an implementation, this threshold is set such that a pressure ofapproximately fifty grams or less is not sufficient to cause the forceconcentrator layer 1102 and the flexible contact layer 502 to initiatethe signal whereas pressures above that threshold are recognizable asinputs. A variety of other implementations and thresholds are alsocontemplated that may be configured to differentiate against a restingpressure and a key strike.

The force concentrator layer 1102 may also be configured to provide avariety of other functionality. The input device 104, for instance, mayinclude the outer layer 402 (e.g., fabric) which as previously describedin relation to FIG. 4 may include indications of operations ofrespective keys, e.g., letters, numbers, and other operations such as“shift,” “return,” navigation, and so on. The force concentrator layer1102 may be disposed beneath this layer. Further, a side of the forceconcentrator layer 1102 that is exposed towards the outer layer 402 maybe configured to be substantially smooth, thereby reducing and eveneliminating witness lines that could result from underlying componentsof the input device 104.

In this way, a surface of the outer layer 402 may be made with increaseduniformity and thus provided a better typing experience with increasedaccuracy, e.g., by promoting a smooth tactile feel without interferencefrom underlying components. The force concentrator layer 1102 may alsobe configured to protect against electrostatic discharge (ESD) tounderlying components of the input device 104. For example, the inputdevice 104 may include a track pad as illustrated in FIGS. 1 and 2 andthus movement across the track pad may generate static. The forceconcentrator layer 1102, however, may protect components of the inputdevice 104 that are exposed beneath the layer from this potential ESD. Avariety of other examples of such protection are also contemplatedwithout departing from the spirit and scope thereof.

Support Layer

FIG. 14 depicts an example implementation 1400 showing the support layer408 that is configured to support operation of the flexible hinge 106 aswell as protect components of the input device 104 during thisoperation. As previously described, the flexible hinge 106 may beconfigured to support various degrees of bending to assume the differentconfigurations. However, materials chosen to form the flexible hinge106, such as to form the outer layers 402, 416 of the flexible hinge 106may be chosen to support a desired “look and feel” and therefore may notprovide desired resiliency against tearing and stretching.

Therefore, in such an instance this could have an effect on operabilityof conductors 1402 that are used to communicatively couple keys andother components of the input device 104 with the computing device 102.For example, a user may grasp the input device 104 with one hand to pullit away from the computing device 102 by disengaging the protrusions 208and magnetic attraction supported by the magnets. Therefore, this couldresult in an amount of force being applied to the conductors that issufficient to break them absent sufficient support from the first orsecond outer layers 402, 416 or other structure.

Accordingly, the input device 104 may include a support layer 408 thatmay be configured to protect the flexible hinge 106 and other componentsof the input device 104. For example, the support layer 408 may beformed of a material that has a higher resistance to tearing andstretching than a material used to form the outer layers 402, 416, e.g.,biaxially-oriented polyethylene terephthalate (BoPET) which is alsoknown as Mylar.

Support provided by the support layer 408 may thus help protect thematerial used to form the outer layers 402, 416 of the flexible hinge106. The support layer 408 may also help protect components disposedthrough the hinge, such as the conductors 1402 used to communicativelycouple the connection portion 202 with the keys.

In the illustrated example, the support layer 408 includes a portion1404 configured to be disposed as part of the input portion 914 of theinput device 104 that includes the keys, track pad, and so on as shownin FIG. 1. The support layer 408 also includes first and second tabs1406, 1408 that are configured to extend from the portion 1404 throughthe flexible hinge 106 to be secured to the connection portion 202. Thetabs may be secured in a variety of ways, such as to include one or moreholes as illustrated through which a protrusion (e.g., screw, pin, andso on) may be inserted to secure the tabs to the connection portion 202.

The first and second tabs 1406, 1408 are illustrated in this example asbeing configured to connect at approximate opposing ends of theconnection portion 202. In this way, undesirable rotational movement maybe restricted, e.g., that is perpendicular to a longitudinal axisdefined by the connection portion 202. Thus, the conductors 1402disposed at a relative midpoint of the flexible hinge 106 in relation tothe edges of the key and connection portion 202 may also be protectedfrom tearing, stretching, and other forces

The support layer 408 in this illustrated example also includes amid-spine portion 1410 that is configured to form part of a mid-spine toincrease the mechanical stiffness of the mid-spine and support a minimumbend radius. Although first and second tabs 1406, 1408 are illustrated,it should be readily apparent that more or fewer tabs may also beemployed by the support layer 408 to support the functionalitydescribed.

Adhesive

FIG. 15 depicts a bottom view 1500 of a pressure sensitive key of FIG. 5as having the flexible contact layer 502 secured at a plurality oflocations along edges of the key. First, second, third, and fourth edges1502, 1504, 1506, 1508 are illustrated in this example as defining anopening 1510 of a spacer layer 508 of a pressure sensitive key. Theopening 1510 as described in relation to FIGS. 5-7 permits the flexiblecontact layer 502 to flex (e.g., bend and/or stretch) through theopening 1510 to contact the one or more conductors 512 of the sensorsubstrate 504.

In the illustrated example, a first securing portion 1512 is illustratedas disposed proximal to the first edge 1502 of the opening 1510.Likewise, second, third, and fourth securing portions 1514, 1516, 1518are illustrated as disposed proximal to respective second, third, andfourth edges 1504, 1506, 1508 of the opening 1510. The securing portionsmay be configured in a variety of ways, such as through use of anadhesive, mechanical securing device (e.g., pins), and so on. Forexample, the adhesive may be applied as a series of dots or other shapesto the spacer layer 508 which is then contacted (e.g., pressed) to theflexible contact layer 502.

Regardless of the technique used to secure the flexible contact layer502 to the spacer layer 508, flexibility may be configured as desired bypermitting portions of the flexible contact layer 502 along the edge ofthe opening to remain unsecured. For instance, the first and secondsecuring portions 1514, 1516 may define sole areas at which the flexiblecontact layer 502 is secured to the spacer layer 508 along therespective first and second edges 1502, 1504. Therefore, flexibility ofthe flexible contact layer 502 may decrease as a distance between apoint of contact of the pressure and a securing portion decreasessimilar to the edge discussion of FIGS. 6 and 7, such as due to slidingof the flexible contact layer over the edge, permit increasedstretching, and so forth.

However, the reverse is also true in that flexibility increases thefurther away pressure is applied from the securing portions. Thus,flexibility along the edges of the opening 1510 may be increased byincluding portions along an edge at which the flexible contact layer 502is not secured (proximally) to the spacer layer 508. Thus, differentarrangements of how the flexible contact layer 502 is secured to thespacer layer 404 may be used to support different amounts of flexibilityat different locations of the flexible contact layer 502.

For example, as illustrated the first and second securing portions 1512,1514 are located closer together than the first and third securingportions 1512, 1516. Accordingly, points (e.g., a midpoint) between thefirst and third securing portions 1512, 1516 may have greaterflexibility than corresponding points (e.g., a midpoint) between thefirst and second securing portions 1512, 1514. In this way, a designermay configure the flexible contact layer 502 to increase or decreaseflexibility at particular locations as desired.

In the example 1600 of FIG. 16, for instance, the second securingportion 1514 is moved from one end of the second edge 1504 to anopposing end of the second edge 1504. Thus, flexibility is increased onthe left upper portion of the key in this example and decreased in theupper right portion of the key. A variety of other examples are alsocontemplated, examples of which are shown in relation to a keyboard inthe following example.

FIG. 17 depicts an example of an adhesive layer 1700 applied as part ofa keyboard having a plurality of keys in which different arrangements ofadhesive are used for different keys. Securing portions in this exampleare illustrated in black lines and dots of adhesive that are used tosecured the flexible contact layer 502 with the spacer layer 506. Asshown, different arrangements of the securing portions may be used toaddress differences in how corresponding keys are likely to be pressed.

For example, as shown the arrangements of adhesive for respective keysin the home row (e.g., keys 43-55) is different than arrangements ofadhesive for a row of keys in the next lower row, e.g., keys 56-67. Thismay be performed to address “where” a key is likely to be pressed, suchas at a center or particular one of the four sides of the key. This mayalso be performed to address “how” a key is likely to be pressed, suchas using a pad of a finger as opposed to a user's fingernail, whichfinger of a user is likely to press the key, and so on. Thus, asillustrated in the example adhesive layer 1700 of FIG. 17, differentarrangements may be used for different rows of keys as well as fordifferent columns of the keys.

The adhesive layer 1700 in this example is also illustrated as formingfirst and second pressure equalization devices 1702, 1704. In thisexample, adhesive is disposed to leave channels formed between theadhesive. Thus, the adhesive defines the channels that form the device.The channels are configured to connect openings 1510 formed as part ofthe pressure sensitive keys between the flexible contact layer 502 andthe sensor substrate 504 to an outside environment of the input device104.

In this way, air may move between the outside environment and theopenings through the channels to generally equalize the air pressure,which may help prevent damage to the input device 104, e.g., when facedwith reduced air pressure in an airplane. In one or moreimplementations, the channels may be formed as a labyrinth having aplurality of bends to protect against outside contaminants from passingthrough the pressure equalization devices 1702, 1704 to the openings1510. In the illustrated example, the pressure equalization devices1702, 1704 are disposed as part of a palm rest of the spacer layer toleverage available space to form longer channels and thus furtherprotect against contamination. Naturally, a wide variety of otherexamples and locations are also contemplated without departing from thespirit and scope thereof.

Nesting

FIG. 18 depicts an example 1800 of surface mount hardware elements 1802that may be used to support functionality of the input device 104. Theinput device 104 may be configured in a variety of ways to support avariety of functionality. For example, the input device 104 may beconfigured to include pressure sensitive keys as described in relationto FIGS. 5-7, a track pad as shown in FIG. 1, or other functionalitysuch as mechanically switched keys, a biometric reader (e.g.,fingerprint reader), and so on.

Accordingly, the input device 104 may include a variety of differenttypes of surface mount hardware elements 1802 or other hardware elementsthat extend above a surface of a substrate (e.g., printed circuit board)to support this functionality. For example, the input device 104 mayinclude a processor 1804 which may be leveraged to perform a variety ofdifferent operations. An example of such an operation may includeprocessing signals generated by the pressure sensitive keys 500 of FIG.5 or other keys (e.g., mechanically switched keys that are not pressuresensitive) into a human interface device (HID) compliant input, such asto identify a particular keystroke. Thus, in this example the inputdevice 104 may perform the processing of the signals and provide aresult of this processing as an input to the computing device 102. Inthis way, the computing device 102 and software thereof may readilyidentify the inputs without modification, such as by an operating systemof the computing device 102.

In another example, the input device 104 may include one or more sensors1806. The sensors 1806, for instance, may be leveraged to detectmovement and/or an orientation of the input device 104. Examples of suchsensors 1806 include accelerometers, magnetometers, inertial measurementunits (IMUs), and so forth.

In a further example, the input device 104 may include a touchcontroller 1808, which may be used to process touch inputs detectedusing one or more keys of the keyboard, the track pad, and so forth. Inyet a further example, the input device 104 may include one or morelinear regulators 1810 to maintain a generally steady voltage forelectrical components of the input device 104.

The input device 104 may also include an authentication integratedcircuit 1812. The authentication integrated circuit 1812 may beconfigured to authenticate the input device 104 for operation with thecomputing device 102. This may be performed in a variety of ways, suchas to share secrets between the devices that are processed by the inputdevice 104 and/or the computing device 102 to perform theauthentication. A variety of other 1814 surface mount hardware elements1802 are also contemplated to support a variety of differentfunctionality.

As previously described, however, inclusion of the surface mounthardware elements 1802 using conventional techniques may have an adverseeffect on an overall thickness of the input device 104. However, in oneor more implementations described herein layers of the input device 104may include nesting techniques to mitigate this effect, furtherdiscussion of which may be found in relation to the following figure.

FIG. 19 illustrates an example implementation 1900 in which the surfacemount hardware element 1802 of FIG. 18 is depicted as being nested inone or more layers of the input device 104. As previously described, theinput device may include top and bottom outer layers 402, 416 which maybe formed to have a desirable tactile feel to a user, such as throughformation using microfiber, and so on. The outer layer 402, forinstance, may be configured using an embossed fabric (e.g., 0.6millimeter polyurethane) in which the embossing is used to provideindications of underlying keys as well as indications of respectivefunctions of the keys.

A force concentrator 404 is disposed beneath the outer layer 402 thatincludes a force concentrator layer 1102 and a plurality of pads 1306,1308 to support respective first and second pressure sensitive keys1302, 1304. The force concentrator 404 may be configured to provide amechanical filter, force direction, and to hide witness lines ofunderlying components.

A pressure sensitive key assembly 406 is disposed beneath the pads 1306,1308 of the force concentrator layer 1102 in this example, althoughother examples are also contemplated in which a force concentrator 404is not utilized. The pressure sensitive key assembly 406 includes layersused to implement pressure sensitive keys. As described in FIG. 5, forinstance, the flexible contact layer 502 may include a force sensitiveink, which through flexing the flexible contact layer 502 may contactone or more conductors of the sensor substrate 504 to generate a signalusable to initiate an input.

The sensor substrate 504 may be configured in a variety of ways. In theillustrated example, the sensor substrate 504 includes a first side onwhich the one or more conductors are configured, such as throughimplementation as traces on a printed circuit board (PCB). A surfacemount hardware element 1802 is mounted to second side of the sensorsubstrate 504 that is opposite the first side.

The surface mount hardware element 1802, for instance, may becommunicatively coupled through the sensor substrate 504 to the one ormore conductors of the first side of the sensor substrate 504. Thesurface mount hardware element 1802 may then process the generatedsignals to convert the signals to HID compliant inputs that arerecognizable by the computing device 102.

This may include processing of analog signals to determine a likelyintention of a user, e.g., to process miss hits, signals from multiplekeys simultaneously, implement a palm rejection threshold, determine ifa threshold has been exceeded that is indicative of a likely key press,and so on. As previously described in relation to FIG. 18, a variety ofother examples of functionality that may be implemented using surfacemount hardware elements of the input device 104 are contemplated withoutdeparting from the spirit and scope thereof.

In order to reduce an effect of a height the surface mount hardwareelement 1802 on an overall thickness of the input device 104, thesurface mount hardware element 1802 may be disposed through one or moreholes of other layers of the input device 104. In this example, thesurface mount hardware element 1802 is disposed through holes that aremade through the support layer 408 and the adhesive layer 410 and atleast partially through the support board 412. Another example is alsoillustrated in FIG. 4 in which holes are formed entirely through each ofthe support layer 408, adhesive layer 410, and the support board 412.

Thus, in this example an overall thickness of the layers of the inputdevice 104 of the force concentrator layer 1102 through the backer layer414 and the layers disposed in between may be configured to have athickness of approximately 2.2 millimeters or less. Additionally,depending on the thickness of the material chosen for the outer layers402, 416 the overall thickness of the input device 104 at a pressuresensitive key may be configured to be approximately at or below threeand a half millimeters. Naturally, other thicknesses are alsocontemplated without departing from the spirit and scope thereof.

Example System and Device

FIG. 20 illustrates an example system generally at 2000 that includes anexample computing device 2002 that is representative of one or morecomputing systems and/or devices that may implement the varioustechniques described herein. The computing device 2002 may be, forexample, be configured to assume a mobile configuration through use of ahousing formed and size to be grasped and carried by one or more handsof a user, illustrated examples of which include a mobile phone, mobilegame and music device, and tablet computer although other examples arealso contemplated.

The example computing device 2002 as illustrated includes a processingsystem 2004, one or more computer-readable media 2006, and one or moreI/O interface 2008 that are communicatively coupled, one to another.Although not shown, the computing device 2002 may further include asystem bus or other data and command transfer system that couples thevarious components, one to another. A system bus can include any one orcombination of different bus structures, such as a memory bus or memorycontroller, a peripheral bus, a universal serial bus, and/or a processoror local bus that utilizes any of a variety of bus architectures. Avariety of other examples are also contemplated, such as control anddata lines.

The processing system 2004 is representative of functionality to performone or more operations using hardware. Accordingly, the processingsystem 2004 is illustrated as including hardware element 2010 that maybe configured as processors, functional blocks, and so forth. This mayinclude implementation in hardware as an application specific integratedcircuit or other logic device formed using one or more semiconductors.The hardware elements 2010 are not limited by the materials from whichthey are formed or the processing mechanisms employed therein. Forexample, processors may be comprised of semiconductor(s) and/ortransistors (e.g., electronic integrated circuits (ICs)). In such acontext, processor-executable instructions may beelectronically-executable instructions.

The computer-readable storage media 2006 is illustrated as includingmemory/storage 2012. The memory/storage 2012 represents memory/storagecapacity associated with one or more computer-readable media. Thememory/storage component 2012 may include volatile media (such as randomaccess memory (RAM)) and/or nonvolatile media (such as read only memory(ROM), Flash memory, optical disks, magnetic disks, and so forth). Thememory/storage component 2012 may include fixed media (e.g., RAM, ROM, afixed hard drive, and so on) as well as removable media (e.g., Flashmemory, a removable hard drive, an optical disc, and so forth). Thecomputer-readable media 2006 may be configured in a variety of otherways as further described below.

Input/output interface(s) 2008 are representative of functionality toallow a user to enter commands and information to computing device 2002,and also allow information to be presented to the user and/or othercomponents or devices using various input/output devices. Examples ofinput devices include a keyboard, a cursor control device (e.g., amouse), a microphone, a scanner, touch functionality (e.g., capacitiveor other sensors that are configured to detect physical touch), a camera(e.g., which may employ visible or non-visible wavelengths such asinfrared frequencies to recognize movement as gestures that do notinvolve touch), and so forth. Examples of output devices include adisplay device (e.g., a monitor or projector), speakers, a printer, anetwork card, tactile-response device, and so forth. Thus, the computingdevice 2002 may be configured in a variety of ways to support userinteraction.

The computing device 2002 is further illustrated as beingcommunicatively and physically coupled to an input device 2014 that isphysically and communicatively removable from the computing device 2002.In this way, a variety of different input devices may be coupled to thecomputing device 2002 having a wide variety of configurations to supporta wide variety of functionality. In this example, the input device 2014includes one or more keys 2016, which may be configured as pressuresensitive keys, mechanically switched keys, and so forth.

The input device 2014 is further illustrated as include one or moremodules 2018 that may be configured to support a variety offunctionality. The one or more modules 2018, for instance, may beconfigured to process analog and/or digital signals received from thekeys 2016 to determine whether a keystroke was intended, determinewhether an input is indicative of resting pressure, supportauthentication of the input device 2014 for operation with the computingdevice 2002, and so on.

Various techniques may be described herein in the general context ofsoftware, hardware elements, or program modules. Generally, such modulesinclude routines, programs, objects, elements, components, datastructures, and so forth that perform particular tasks or implementparticular abstract data types. The terms “module,” “functionality,” and“component” as used herein generally represent software, firmware,hardware, or a combination thereof. The features of the techniquesdescribed herein are platform-independent, meaning that the techniquesmay be implemented on a variety of commercial computing platforms havinga variety of processors.

An implementation of the described modules and techniques may be storedon or transmitted across some form of computer-readable media. Thecomputer-readable media may include a variety of media that may beaccessed by the computing device 2002. By way of example, and notlimitation, computer-readable media may include “computer-readablestorage media” and “computer-readable signal media.”

“Computer-readable storage media” may refer to media and/or devices thatenable persistent and/or non-transitory storage of information incontrast to mere signal transmission, carrier waves, or signals per se.Thus, computer-readable storage media refers to non-signal bearingmedia. The computer-readable storage media includes hardware such asvolatile and non-volatile, removable and non-removable media and/orstorage devices implemented in a method or technology suitable forstorage of information such as computer readable instructions, datastructures, program modules, logic elements/circuits, or other data.Examples of computer-readable storage media may include, but are notlimited to, RAM, ROM, EEPROM, flash memory or other memory technology,CD-ROM, digital versatile disks (DVD) or other optical storage, harddisks, magnetic cassettes, magnetic tape, magnetic disk storage or othermagnetic storage devices, or other storage device, tangible media, orarticle of manufacture suitable to store the desired information andwhich may be accessed by a computer.

“Computer-readable signal media” may refer to a signal-bearing mediumthat is configured to transmit instructions to the hardware of thecomputing device 2002, such as via a network. Signal media typically mayembody computer readable instructions, data structures, program modules,or other data in a modulated data signal, such as carrier waves, datasignals, or other transport mechanism. Signal media also include anyinformation delivery media. The term “modulated data signal” means asignal that has one or more of its characteristics set or changed insuch a manner as to encode information in the signal. By way of example,and not limitation, communication media include wired media such as awired network or direct-wired connection, and wireless media such asacoustic, RF, infrared, and other wireless media.

As previously described, hardware elements 2010 and computer-readablemedia 2006 are representative of modules, programmable device logicand/or fixed device logic implemented in a hardware form that may beemployed in some embodiments to implement at least some aspects of thetechniques described herein, such as to perform one or moreinstructions. Hardware may include components of an integrated circuitor on-chip system, an application-specific integrated circuit (ASIC), afield-programmable gate array (FPGA), a complex programmable logicdevice (CPLD), and other implementations in silicon or other hardware.In this context, hardware may operate as a processing device thatperforms program tasks defined by instructions and/or logic embodied bythe hardware as well as a hardware utilized to store instructions forexecution, e.g., the computer-readable storage media describedpreviously.

Combinations of the foregoing may also be employed to implement varioustechniques described herein. Accordingly, software, hardware, orexecutable modules may be implemented as one or more instructions and/orlogic embodied on some form of computer-readable storage media and/or byone or more hardware elements 2010. The computing device 2002 may beconfigured to implement particular instructions and/or functionscorresponding to the software and/or hardware modules. Accordingly,implementation of a module that is executable by the computing device2002 as software may be achieved at least partially in hardware, e.g.,through use of computer-readable storage media and/or hardware elements2010 of the processing system 2004. The instructions and/or functionsmay be executable/operable by one or more articles of manufacture (forexample, one or more computing devices 2002 and/or processing systems2004) to implement techniques, modules, and examples described herein.

CONCLUSION

Although the example implementations have been described in languagespecific to structural features and/or methodological acts, it is to beunderstood that the implementations defined in the appended claims isnot necessarily limited to the specific features or acts described.Rather, the specific features and acts are disclosed as example forms ofimplementing the claimed features.

What is claimed is:
 1. An input device comprising: a sensor substratehaving one or more conductors disposed on a first side of the sensorsubstrate and one or more surface mount hardware elements disposed on ansecond side of the sensor substrate that is opposite the first side; aflexible contact layer spaced apart from the sensor substrate andconfigured to flex in response to an application of pressure to contactthe sensor substrate to initiate an input for a computing device that iscommunicatively coupled to the input device; and one or more layersdisposed on the second side of the sensor substrate, the one or morelayers having one or more openings therein such that at least a portionof the one or more surface mount hardware elements is disposed throughthe one or more openings thereby nesting the one or more surface mounthardware elements within the one or more layers.
 2. An input device asdescribed in claim 1, wherein the one or more layers include a supportboard.
 3. An input device as described in claim 2, wherein the one ormore layers also include a support layer disposed between the supportboard and the sensor substrate, the support layer configured to extendthrough a flexible hinge to a connection portion that is configured toprovide a communicative coupling to the computing device.
 4. An inputdevice as described in claim 3, wherein the connection portion isconfigured to implement a removable physical coupling with the computingdevice using one or more magnetic coupling devices.
 5. An input deviceas described in claim 1, wherein the one or more surface mount hardwareelements include a processor.
 6. An input device as described in claim1, wherein the one or more surface mount hardware elements include asensor.
 7. An input device as described in claim 6, wherein the sensoris configured as an accelerometer.
 8. An input device as described inclaim 1, wherein the one or more surface mount hardware elements includeone or more linear regulators.
 9. An input device as described in claim1, wherein the one or more surface mount hardware elements include anauthentication integrated circuit that is configured to authenticate theinput device for operation with the computing device.
 10. An inputdevice comprising: a pressure sensitive key assembly including asubstrate having a plurality of hardware elements secured to a surfacethereof and extend above the surface; and one or more layers disposedproximal to the surface, the one or more layers having respectiveopenings configured to nest the one or more surface mount hardwareelements therein.
 11. An input device as described in claim 10, whereinthe one or more layers include a support board.
 12. An input device asdescribed in claim 11, wherein the one or more layers also include asupport layer disposed between the support board and the sensorsubstrate, the support layer configured to extend through a flexiblehinge to a connection portion that is configured to provide acommunicative coupling to the computing device.
 13. An input device asdescribed in claim 12, wherein the connection portion is configured toimplement a removable physical coupling with the computing device usingone or more magnetic coupling devices.
 14. An input device as describedin claim 10, wherein the one or more hardware elements are configured asa surface mount hardware element.
 15. An input device as described inclaim 14, wherein the surface mount hardware element is an integratedcircuit configured as a processor or authentication integrated circuitthat is configured to authenticate the input device for operation withthe computing device.
 16. An input device as described in claim 10,wherein the one or more hardware elements include an accelerometer. 17.An input device as described in claim 10, wherein the one or morehardware elements include one or more linear regulators.
 18. A keyboardcomprising: a key assembly including a substrate having a hardwareelement secured to a surface thereof, the hardware element configured toprocess signals received from the key assembly into a respective humaninterface device (HID) compliant output; and one or more layers disposedproximal to the surface of the sensor substrate, the one or more layershaving one or more openings therein such that at least a portion of thehardware element is disposed through the one or more openings therebynesting the one or more hardware elements within the one or more layers.19. A keyboard as described in claim 18, wherein the key assembly alsoincludes another hardware element secured to the surface that isconfigured as an accelerometer.
 20. A keyboard as described in claim 18,wherein the key assembly also includes another hardware element securedto the surface that is configured as a touch controller.